The goal of this program is to train MD and PhD postdoctoral fellows in biomedical research as it applies to Blood Coagulation and Vascular Biology. We offer a multi-disciplinary program that consists of didactic instruction, seminars and supervised research. Important elements of the curriculum are supervision by faculty advisors, formal course work, interactions between trainee and the faculty, and interactions between the trainee and his peers. Dr. Bruce Furie is the Program Director and Dr. Barbara C. Furie is the Associate Program Director. Faculty of the program, all members of the Dept of Medicine at Beth Israel Deaconess Medical Center and Harvard Medical School, are from the Divisions of Hemostasis-Thrombosis, Hematology-Oncology, Experimental Medicine, Molecular Medicine and Signal Transduction. MD trainees are selected from about 120 applicants each year. Only those applicants with an explicit commitment to a career in academic medicine are selected. This training plan is integrated into the hematology training program for physicians planning careers in academic medicine. It consists of a minimum of two years of supervised bench research and didactic instruction after completion of the major portion of hospital-funded clinical subspecialty training. We also receive over 300 applications per year from candidates with the PhD degree or physicians applying solely for research training. A subset of these applicants do not meet eligibility requirements for this training grant. The design of the program takes into account (a) the need for physicians to acquire knowledge of advances in molecular and cell biology; (b) the need for an extended training experience to allow fellows to develop sophistication in modern, complex biomedical research; (c) the need for PhD scientists to understand the biology and pathobiology of the vascular system. This grant, funded for the past five years, represents a continuation of T32 HL07437 which had been active at New England Medical Center for 20 years. During the past five years, this application has supported 19 trainees (2 MD, 5 MD PhD, 12 PhD). Of these, 7 have faculty positions, 2 have positions in the biotechnology industry and 10 remain in various aspects of training. This training program has proved exceptionally successful, and has been greatly enriched by its move to Harvard Medical School and the addition of committed training faculty who serve as mentors for trainees.